GNU Testimonials—Robert E. A. Harvey

From: Robert E. A. Harvey

I work on research ships, mainly deep seismic acquisition, but other types
as well. The story I am about to tell is of a single piece of GNU
software. Tar. For many years we have been using systems with disk stacks
containing disks no more than 3 Gb in size, and the application code has
facilities to span data across disks. But for backup, it calls a shell
script which calls tar. And does so on a disk-by-disk basis. We have been
taring to Exabyte 2500 drives, and fortunately no one disk was bigger than
would fit on a tar tape.

The world changes, and things move on. Because of a monster project last
year I was forced to replace several of the disks in the stack with 180Gb
ones. The application code coped, but the backup needed very careful human
intervention instead of using the facilities from the application—because
now it was easy to launch a backup that would not fit on one tape.

The solution? GNU tar. GNU tar has allowed us to do two things in one go:
to split backups across more than one tape, and to connect directly to an
IBM 3590 tape drive on another workstation for larger capacity. This was
made possible, too, by the well-written application code whose GUI merely
calls a shell script, and by some of the basic modularity of Unix. But
without GNU tar it could not have been done. A two kilo-euro investment in
software, hardware, training, and installtion on the vessel has been rescued
from obselescence by me—with some help from GNU tar.

GNU tar is an enhanced version of standard Unix tar. But the enhancements
are sensible, and merely looking at the help output one can see that they
have been made by practical, experienced, people working with the code they
write. The code is solid, reliable, and achieves exactly what it sets out
to do. And it is familiar enough that anyone can use it.

How long did it take me to make this astonishing change? Twenty hours to
download some binary packages to the vessel. And around 3 minutes to
install them. Another hour for the changes to the application script, and
6 hours to test. (Have you ever tried writing 8.6GB of data?).

I have been using GNU, and GNU/Linux, software for many years: since my days
at Rockwell Automation at least, call that 1984. I just thought it was time
to say thank you to the originators of some of the most useful bits of code
on the planet.